1. Field of the Invention
The present invention involves the field of medical devices. More particularly, it involves the field of medical devices used in chiropractic. Even more particularly, it relates to chiropractic adjustment tools used to move bones and relieve muscle spasms and stress.
2. Prior Art
As is well-known in the chiropractic art, the spines or other bones of humans sometimes go out of alignment or are otherwise mis-adjusted. This can lead to discomfort and, sometimes, additional physical symptoms. In such cases, an adjustment of the spine or other bone to a healthy alignment can have substantial therapeutic effects.
Several attempts have been made to provide hand-held or other small devices to assist in adjusting a patient's spine or other bone by the use of impacts against the bone. However, each of these devices provides only a single impact per application, as described below.
U.S. Pat. No. 4,016,873, issued Apr. 12, 1977 to Anderson, is entitled "PNEUMATIC IMPACTER." The patent teaches a pneumatic gun-type device with an impact cylinder which is released when a trigger is squeezed. The impact cylinder, when released by the trigger, is extended under pressure until it makes contact with a surface. The pressure is adjustable to permit the user of the device to set the pressure desired for a specific treatment. The device provides one impact per pull of the trigger.
U.S. Pat. No. 4,498,464, issued Feb. 12, 1985 to Morgan, Jr., is entitled "CHIROPRACTIC INSTRUMENT." The patent teaches a manually-operated instrument used to provide an impact to a specific surface of a body. The instrument has a plunger or cylinder-type device with a striking surface. The cylinder is movable within a hand-held chamber. The movement of the cylinder is controlled by a spring, which is contained within the chamber, and permits an adjustment of the tension applied by the cylinder. In use, a user of the device manually strikes it against a patient's body. The spring adjustment permits the user to determine the impacting pressure the person wishes to make on the patient's body. The device provides one impact per application.
U.S. Pat. No. 4,669,454, issued Jun. 2, 1987 to Shamos, is entitled "PERCUSSING CHIROPRACTIC DEVICE HAVING ADJUSTABLE SPRING FORCE." The patent teaches a body-impact device similar to the Morgan device discussed above. The device consists of a hand-held chamber having an anvil at one end and a spring-biased hammer mounted in the chamber. An elongated spindle is connected to the hammer for drawing the hammer away from the anvil into a loaded position in which the spring is compressed. Upon release of the spring, the hammer strikes the anvil, which strikes the patient's body. The level of tension is adjustable to provide impacts of varying strength to a patient's body. The device provides one impact per application.
As can be seen from the above, the prior art has provided several single-impact chiropractic devices. However, the prior art has not disclosed a multiple-impact device for providing therapeutic pressure to a patient's body. Multiple impacts are desirable because of the cumulative effect of the treatment provided therewith. The present invention is directed to this shortcoming in the prior art.